XFA 600
Thermal Diffusivity
Thermal Conductivity
Information of the thermo physical properties of materials and heat transfer optimization of final products is becoming more and more vital for industrial applications. Over the past few decades, the flash method has developed into the most commonly used technique for the measurement of the thermal diffusivity and thermal conductivity of various kinds of solids, powders and liquids.
Application areas are electronic packaging, heat sinks, brackets, re- actor cooling, heat exchangers, thermal insulators and many others.
Trouble-free sample preparation, small required sample dimensions, fast measurement times and high accuracy are only a few of the
Thermal Diffusivity, Thermal Conductivity
advantages of this non-contact and non-destructive measurement technique.
LINSEIS offers a variety of instruments to measure the Thermal Diffusi- vity. The XFA 600 provides a cost effective solution for the temperature range -125 up to 600°C.
As for the calculation of the thermal conductivity, the specific heat and densitiy are requiered, LINSEIS offers a full range of Differential Scan- ning Calorimeters and Dilatometers.
Gua rded Heat Flow Meter Hot Wi re Flash
1000
100
10.0
1.0
0.1
0.01
0.001
Gua rded Heat Flow Meter Hot Wi re Flash
-180–650°C
-150–300°C
-125–1600°C
Diamond
Aluminum, Graphite Silicon
Iron, Steel
Alumina, Carbon Bricks Silicon nitride
Alumina Silicates
Porous Ceramics, Refractories Concrete, Glass, Fire clay Water
Wood, Polymers, Coal Building boards, Oils Fiber boards, Fiber Insulations Air, Polystyrene, PUR Foams
Vacuum Isolation
Thermal Conductivity W/(m·K)
Methods
Principle
The sample is positioned on a sample robot, located in a furnace. The furnace is then held at a predetermined temperature. At this tempera- ture the sample surface is then irradiated with a programmed energy pulse (laser or xenon flash). This energy pulse results in a homogeneous temperature rise at the sample surface. The resulting temperature rise of the rear surface of the sample is measured by a very sensitive high speed IR detector and thermal diffusivity values are computed from the temperature rise versus time data. If the density (r) is identified, the thermal conductivity can be calculated:
Thermal Diffusivity & Conductivity measuring range
The Xenon Flash technique covers the widest measuring range of all techniques, 0.1 up to 2000W(m*K) for Thermal Conductivity and 0.01 up to 1000 mm
2/s for Thermal Diffusivity.
Accuracy & Repeatability
Highest Accuracy (+/-2.2% for thermal diffusivity, +/-4% for specific heat and +/-5% for thermal conductivity) and repeatability (+/-2% for thermal diffusivity, +/-3.5% for specific heat and +/-4% for thermal conductivity). Values may vary for special applications!
Multilayer evaluation
The powerful software package enables the evaluation of two or three layer systems.
Correspondence with International Standards
The LINSEIS XFA operate in agreement with national and international standards such as ASTM E-1461, DIN 30905 and DIN EN 821.
Absolute technique
The method used is an absolute measurement technique (for thermal diffusivity) hence there is no need to calibrate the system.
Speed and Flexibility
The combination of sample robot and test method allows unbeaten measurement turnaround time. A typical measurement for up to 6 samples takes only a few hours.
System Design
LINSEIS is offering an unparalleled modular system design for this Thermophysical properties Analyzer. It is possible to upgrade the tem-
perature range (exchangeable furnaces/ measuring system) and the detector (InSb). This enables the user to start with a cost effective solution and upgrade the system whenever the budget allows or
the measurement task requires it.
l(T)=a(T)·c p (T)·r(T)
Software
All thermo analytical devices of LINSEIS are PC controlled, the individual software modules exclusively run under Microsoft
®Windows
®operating systems. The complete software consists of 3 modules: temperature control, data acquisition and data evaluation. The LINSEIS 32 – bit soft- ware encounters all essential features for measurement preparation, execution and evaluation, just like with other thermo analytical experi- ments. Due to our specialists and application experts LINSEIS was able to develop this easy understandable and highly practical software.
General Software
• Fully compatible MS
®Windows™ 32 – bit software
• Data security in case of power failure
• Thermocouple break protection
• Evaluation of current measurement
• Curve comparison
• Storage and export of evaluations
• Export and import of data ASCII
• Data export to MS Excel
• Multi - method analysis (DSC TG, TMA, DIL, etc.)
• Programmable gas control
Evaluation Software
• Automatic or manual input of related measurement data:
(density), Cp (Specific Heat)
• Model wizard for selection of the appropriate model
• Finite pulse correction
• Heat loss correction
• Multilayer model
• Determination of contact resistance
• Cp (Specific Heat) determination by comparative method
Measurement Software
• Easy and user-friendly data input for temperature segments, gases etc.
• Controllable sample robot
• Software automatically displays corrected measurements after the energy pulse
• Fully automated measurement procedure for multi sample
measurements
Laser
The used Nd: YAG Laser has a power output of 10J/pulse. Both the po- wer and the pulse length can be easily adjusted by the Software. The system design includes all safety features to guarantee a secure ope- ration.
Xenon Flash Lamp
The Xenon fl ash lamp offers a cost effective solution to perform Thermo- physical property measurements. The integrated lamp delivers a maxi- mum energy pulse of 10J/pulse.
Sample robot
The fully motorized sample robot can carry up to 6 samples (10 or 12.7 mm round or 10 mm square) or up to 3 samples (25.4 mm round). This design allows unbeaten sample throughput and sample size at the same time. Liquid samples can be measured in special containers. Other sam- ple geometries or sizes are certainly possible on request.
Environmental options
The system can be operated under vacuum 10E
-5mbar, oxidizing or
controlled gas control box (2, 3 or 4 gases) can be attached to generate specifi c atmospheres.
Furnace
The LFA/XFA unit can be equipped with 7 different furnaces. All furnaces are easily exchangeable.
Detectors
The system can be either equipped with an InSb detector or with a MCT detector. Both are easily user exchangeable. Both detectors can be or- dered with an 8 hour or 24 hour Dewar. For even longer measurements
Analyzer Furnace Model Temperature
LFA 1000 Cryo-Furnace -125 up to 500°C
XFA 300 IR Furnace RT up to 300°C
LFA 1000/XFA 600 Furnace 1 RT up to 600°C
LFA 1000 Furnace 2 RT up to 1250°C
LFA 1000 Furnace 3 RT up to 1600°C
LFA 1000 HT Furnace 4 RT up to 2000°C
LFA 1000 HT Furnace 5 RT up to 2800°C
System Design
Detector
Iris
Furnance
Sample Carrier
Xenon Flash
Laser
Graphite (polycrystalline)
Graphite is an excellent material for checking the performance of a La- ser/Xenon Flash Thermal Analyzer. The analyzed material shows a maxi- mum thermal diffusivity around room temperature. The specific heat of the material which can be analyzed by comparative method or by using a DSC / High Temperature DSC shows a significant increase at higher temperatures.
Applications
120 110 100 90 80 70 60 50 40 30 20
120 110 100 90 80 70 60 50 40 30 20
0 100 200 300 400 500 600 Thermal Diffusivity [mm2/s]
Temperature [°C]
Thermal Conductivity [W/(m·K)] Specific Heat [J/(g·K)]
2.0 1.8 1.6 1.4 1.2 1.0 0.9 0.8 0.6 0.4 0.2 0.0 Thermal Diffusivity Thermal Conductivity Specific Heat
Aluminum and Copper
The pure metals Copper and Aluminum are used in this example to demonstrate the performance of the Linseis Laser Flash device. The measurement results of the two materials are compared with literature values. The measured results vary within 2% of the given literature va- lues; this demonstrates the excellent performance of the instrument.
120 110 100 90 80 70 60 50 Thermal Diffusivity [mm2/s]
0 100 200 300 400 500 600 Temperature [°C]
Copper (Messurement) Aluminium (Messurement) Copper (Literature) Aluminium (Literature)
Isotropic Graphite (AIST))
This graph shows the Thermal Diffusivity values measured on a LINSEIS LFA 1000 compared to the values measured at AIST* Japan. The lite- rature values of the used Isotropic Graphite from AIST* the measured results on the LFA 1000 vary by less than 2%.
*(National Institute of Advanced Industrial Science and Technology, Japan)
1.0
0.8
0.6
0.4
0.2
0.0 Thermal Diffusivity [cm2/s]
300 500 700 900 1100 1300 1500 Temperature [K]
AIST LFA 1000
